
ecological validity. Naturalistic designs are used to
mimic real-life as closely as possible, therefore being
characterized by a minimum of lifestyle rules for par-
ticipants and no interference of the investigators with
participants’ activities (Verster et al., 2019). We fol-
lowed the principles suggested when studying secu-
rity and privacy with regard to user behavior (Krol et
al., 2016). However, due to ethical concerns we did
not let participants pay with their money to purchase a
product, instead we provided fake payment informa-
tion for each participant.
For the observational part we implemented three
different versions of an online store, only varying
in their trust indicators (one “trustworthy store”, one
“veiled scam store” and one “obvious scam store”;
see Table 1). The implemented trust indicators in
the three online stores were selected based on an ini-
tial list derived from literature, followed by a discus-
sion and selection process with stakeholders (orga-
nizations dealing with e-commerce, including scam
stores) considering relevance and practicability. In
addition, we varied minor visual aspects of the dif-
ferent online stores (e.g., banner images, footer style,
and color) to make them more distinct for the partici-
pants and to make the changes in trust indicators less
obvious. Invited participants first visited the study
landing page including a description of the study pur-
pose, privacy statement, and the task they had to per-
form, namely to buy a backpack in any of the three
available stores for an upcoming trip. For each partic-
ipant we randomly selected if the instruction text in-
cluded time pressure or not. The time pressure manip-
ulation was implemented by informing participants
that they only have limited time to purchase the prod-
uct and that a hidden timer is running which would
end the study. However, no timer was implemented in
the study, the instruction was only formulated to in-
crease time pressure for the participants. Participants
were informed that the study investigates their online
shopping behavior, without naming online shopping
scam/trust as the primary focus of the study. This pro-
cedure was chosen to prevent participants from being
primed about the trust indicators of the study. Partic-
ipants were instructed to use their desktop computer
rather than their mobile phone or tablet to minimize
contextual factors impacting data quality.
Participants navigated through the online stores at
their own discretion. Nine different products (back-
packs) with picture, name and price were shown on
each shop’s main page.
For each product a details page existed, compris-
ing two or three pictures of the backpack, a short
product description, and stock/delivery time. In the
footer of each store, links to various subpages such
as the imprint and the terms and conditions, trust-
marks (one e-commerce trustmark and one trustmark
by a technical inspection agency) and payment logos
were presented. After participants added a product to
the basket and started the checkout process, a page
summarized the products in the basket and the total
sum of their order. On the next page participants had
to choose between different payment methods before
being redirected to a page presenting pre-filled fictive
shipping and billing address as well as payment infor-
mation. Upon confirming their simulated order and
payment, they were redirected to the survey page de-
scribed in the following section.
3.2.2 Survey
Immediately after the final order confirmation, par-
ticipants were asked to fill in a survey collecting
sociodemographic information (gender, age, educa-
tional level, profession) and behavioral variables (fre-
quency of private Internet usage and Internet usage
at work, purchase behavior, frequency of online pur-
chase). Furthermore, participants were asked to an-
swer if they felt time pressure during the task and if
it had an impact on their purchase behavior, as well
as to rate several impact factors (price, website de-
sign, name of the online store, product design, prod-
uct description, banner, payment methods, subjective
experienced seriousness of the website, general terms
and conditions, cancellation terms, shipping terms,
imprint, trustmarks) on their purchase decision on a
Likert scale of one (no impact) to five (big impact).
All items within the survey were mandatory.
3.3 Recruitment and Sample
To recruit participants, companies and institutions in
Austria were contacted via email including the study
link and a short description. German-speaking partic-
ipants with and without experience in online shopping
above the age of 18 were included. Sample character-
istics can be found in Table 2.
3.4 Data Analysis
All analyses were run with Stata 14.2. For as-
sociations between variables we used Chi-squared
test, Wilcoxon rank-sum test, Kruskal–Wallis one-
way analysis of variance, regression analysis or analy-
sis of variances (ANOVA) depending on their level of
measurement and the number of group comparisons.
We accept a 5% type 1 error rate for each single test as
a feature of our study. Of 651 participants who com-
pleted the study, five had to be excluded due to ques-
tionable validity of the data (e.g., started in one store
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